1. Field of the Invention
This invention relates to a control device for a hybrid construction machine such as, for example, a power shovel.
2. Description of the Related Art
Various types of devices for combining the discharge flow of the main pump and the discharge flow of the sub-pump to assist the output of the pump to be delivered to an actuator have been long known.
Most of such devices are configured to provide an approximately equal assist force to each of the actuators connected to the circuit.
However, when a rotating motor alone is operated, the assist force provided by the sub-pump is not much required. For example, during the acceleration of the rotating motor, a pressure is required, but a flow rate is not much required. Whereas, upon entry into the steady rotating state after the completion of acceleration, the pressure is not much required, but the flow rate is mainly required in order to maintain the speed.
In either case, the related-art control devices for construction machines controls the assist from the sub-pump in the single operation of the rotating motor which does not much require the assist from the sub-pump, as well as in other regular working operations than the single operation of the rotating motor.
[Patent Literature 1] JP-A 2002-275945